U.S. patent number 6,304,219 [Application Number 09/380,131] was granted by the patent office on 2001-10-16 for resonant antenna.
Invention is credited to Lutz Rothe.
United States Patent |
6,304,219 |
Rothe |
October 16, 2001 |
Resonant antenna
Abstract
An antenna for receiving and transmitting electromagnetic
microwaves having .lambda. wavelengths consisting of a substrate
layer (10) made of a low dielectric material which bears on one
side a conductive ground plane (1) and whose opposite side is
conductively structured as micro-strip circuits. The conductive
structure (S) has an elongate conductor section (3, 3a, 3b, R, Ra,
Rb) which acts as a resonator and whose length (L.sub.R) is shorter
than .lambda..sub.c /4. One end of said conductor section is
conductively connected to the ground plane (8, 1) and its other end
is conductively connected to at least another conductor section (2,
2a, 2b, 4, 42a, 42b, 46a, 46b, K) used as an end capacitor to
adjust resonance conditions. The conductor section (3, 3a, 3b, R,
Ra, Rb) which acts as a resonator is connected to the inner
conductor of a coaxial optical fiber and the outer conductor or the
coaxial optical fiber is connected to the ground plane (1).
Inventors: |
Rothe; Lutz (D-06132 Halle
(Saale), DE) |
Family
ID: |
7821434 |
Appl.
No.: |
09/380,131 |
Filed: |
November 22, 1999 |
PCT
Filed: |
February 24, 1998 |
PCT No.: |
PCT/EP98/01040 |
371
Date: |
November 22, 1999 |
102(e)
Date: |
November 22, 1999 |
PCT
Pub. No.: |
WO98/38694 |
PCT
Pub. Date: |
September 03, 1998 |
Foreign Application Priority Data
|
|
|
|
|
Feb 25, 1997 [DE] |
|
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197 07 535 |
|
Current U.S.
Class: |
343/700MS;
343/846 |
Current CPC
Class: |
H01Q
1/38 (20130101); H01Q 1/24 (20130101); H01Q
1/40 (20130101); H01Q 13/08 (20130101) |
Current International
Class: |
H01Q
1/24 (20060101); H01Q 1/40 (20060101); H01Q
13/08 (20060101); H01Q 1/38 (20060101); H01Q
1/00 (20060101); H01Q 001/38 () |
Field of
Search: |
;343/7MS,702,826,829,830,795,846,848 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Ho; Tan
Attorney, Agent or Firm: Woodbridge & Associates, P.C.
Woodbridge; Richard C.
Claims
What is claimed is:
1. An antenna for receiving and transmitting of electromagnetic
microwaves of wavelength .lambda., consisting of a substrate layer
(10) made of low-dielectric material, which on one side is provided
with conductive ground plane (1) and whose opposite side is a
conductive structure in the form of micro-strip circuits, and
charaterized by the face that the conductive structure (S) has a
longitudinal conductor section (3, 3a, 3b, R, Ra,Rb) as resonator,
whose length (L.sub.R) is shorter than .lambda..sub.g /4, and which
is conductively connected with the ground plane (B, 1) at its end,
and whose other end is conductively connected with at least one
other conductor section (2, 2a, 2b, 4, 42a, 42b, 46a, 46b,K), which
serves as end capacitance for the purpose of adjusting the
resonance condition, whereby the resonator conductor section (3,
3a, 3b, R, Ra, Rb) is in connection with the ground plane (1) using
an internal conductor of a coaxial wave guide and the external
conductor of the coaxial wave guide.
2. An antenna as described in claim 1 and characterized by the fact
that the at least one additional conductor section (2, 2a, 2b, 4,
42a, 42b, 46a, 46b, K) is constructed as a micro-strip circuit and
arranged parallel to the resonator conductor section (3, 3a, 3b, R,
Ra, Rb).
3. An antenna as described in claim 1 and characterized by the fact
that the resonator conductor section (3, 3a, 3b, R, Ra, Rb) is
conductively connected with an additional conductor section (2, 2a,
2b, 4, 42a, 42b, 46a, 46b, K) in such manner that the two conductor
sections section (2, 2a, 2b, 4, 42a, 46a, 46b, K; 3, 3a, 3b, R, Ra,
Rb) together with the connection conductor section (17, 41a, 45a,
45b, 49a, 49b) connected to them form a U with arms of equal or
different lengths.
4. An antenna as described in claim 1 and characterized by the fact
that at least two additional conductor sections (2, 2a, 2b, 4, 42a,
42b, 46a, 46b, K), which are particularly arranged parallel to the
resonator conductor section (3, 3a, 3b, R, Ra, Rb), each connected
by its one end with the end of the resonator conductor section (3,
3a, 3b, R, Ra, Rb) via a connection circuit (7, 41a, 41b, 45a, 45b,
49a, 49b) running transversely to the longitudinal line of symmetry
of the resonator conductor section (3, 3a, 3b, R, Ra, Rb), whereby
the other conductor sections (2, 2a, 2b, 4, 42a, 42b, 46a, 46b, K)
are distributed either on one side or on both sides, whereby
particularly the length (L.sub.k) of the other conductor section
(2, 2a, 2b, 4, 42a, 42b, 46a, 46b, K) is different.
5. An antenna as described in claim 1 and characterized by the fact
that the one end of the resonator conductor section (3, 3a, 3b, R,
Ra, Rb) is connected to the ground plane (1) by at least one
terminal pin passing through the substrate layer (10, 10a,
10b).
6. An antenna as described in claim 1 and characterized by the fact
that the one end of the resonator conductor section (3, 3a, 3b, R,
Ra, Rb) is connected via a conductive coating (12, 12ab) to the the
transverse surface of the substrate layer (10, 10a, 10b).
7. An antenna as described in claim 1 and characterized by the fact
that at least on additional conductor section (2, 2a, 2b, 4, 42a,
42b, 46a, 46b, K) is formed as straight linear, angular,
bent/curved, wavelike, zigzag, or right-angular.
8. An antenna as described in claim 1 and characterized by the fact
that that for the purpose of adjustment of the resonator condition,
at least one additional, essentially U-shaped conductor section
(19, 20, 21; 23-28; 30-35; 31', 33', 35'; 48a/b-50a/b) is arranged
on the substrate layer (10), whereby one arm (21, 27, 28, 34, 35,
35', 50a, 50b) of said U-shaped additional conductor section
impinges into the opening formed by the resonator section (3, 3a,
3b, R, Ra, Rb) and the additional conductor section (2, 2a, 2b, 4,
42a, 42b, 46a, 46b, K) and the end of the other arm (19, 23, 24,
30, 31, 48a, 48b) of the additional conductor section is connected
to the ground plane (1, 18, 22, 29, 47, 47').
9. An antenna as described in claim 8 and characterized by the fact
that the additional U-shaped conductor section (Rb, 41b, 42b) is an
antenna for transmitting and receiving electromagnetic waves,
whereby the waves are coupled in or coupled out from the conductor
section (Rb) connected to the ground plan (1, 40b) in such a way
that the interleaving structures of the antennas affect the
resonance conditions and/or tuning of the individual resonators by
reciprocal electromagnetic coupling and an expanded frequency range
is achieved.
10. An antenna as described in claim 1 and characterized by the
fact that several antennas for transmitting and/or receiving
different wavelengths are arranged on the substrate layer (10, 10a,
10b) alongside each other and which are each coupled with a coaxial
wave guide.
11. An antenna as described in claim 1 and characterized by the
fact that several antennas each separated by at least one substrate
layer (10a) are arranged on top of one another.
12. An antenna as described in claim 1 and characterized by the
fact that that the internal conductor (13, 13a, 13b) of the coaxial
wave guide is lead through an aperture (15, 15a, 15b) in the ground
plane (1) and a recess in the layer (10, 10a, 10b) and connected to
the resonator conductor section (3, 3a, 3b, R, Ra, Rb), whereby the
input impedance of the antenna is determined over the point (9) of
the in-coupling along the longitudinal line of symmetry of the
resonator conductor section (3, 3a, 3b, R, Ra, Rb).
13. An antenna as described in the foregoing claim 12 and
characterized by the fact that the aperture (15, 15a, 15b) is
circular, slit-like, or rectangular.
14. An antenna as described in claim 1 and characterized by the
fact that the tuning of the antenna as a result of dielectric
environmental factors is compensated over the length of the
additional conductor sections (19, 20, 21; 23-28; 30-35; 31', 33',
35'; 48a/b-50a/b) and/or by the antennas arranged additionally on
the substrate.
15. An antenna as described in claim 1 and characterized by the
fact that that the degree of tuning of the antenna as a consequence
of dielectric environmental factors is affected or minimized by the
application of a dielectric layer (11) of a defined dielectric
number and of a defined geometry, in particular thickness.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention concerns an antenna intended for reception and
transmission of electromagnetic microwaves in the wavelength range
of .lambda. and consisting of a substrate layer of low dielectric
material that is structured on one side with a conductive ground
plane and whose opposing side is conductive in the form of
micro-strip circuits.
The area of application of the invention extends fundamentally to
the mobile communications and handheld technologies within the
spectral range of between 890 MHz and 960 MHz or 1710 MHz and 1890
MHz whereby the components described in the invention are
integrated into the respective terminal devices and handheld
technologies.
2. Description of Related Art
Familiar antenna solutions for the area of mobile communications
applications are based on linear antenna designs in the form of
single-pole applications in shortened or unshortened execution.
These linear antennas are familiar both as externally installed
aerial antennas [Bordantennen] an as components that are integrated
directly with the terminal device, as well as those affected by
various directional factors and effectiveness, whereby these
components are exclusively omnidirectional at the azimuth level.
Familiar flat antenna solutions are based on planar arrangements
similar to dipolar configurations whose radiation pattern is
irregular and exhibits and, in conjunction with the respective
antenna support or antenna body, the characteristics of a
significant radiation field deformations. The radiation field
properties relevant to the area of application are clearly inferior
to those of the classical linear antenna. Likewise, fade or tune
out properties of the radiation pattern are not demonstrable.
Furthermore there are no known solutions, whose electromagnetic or
radiation characteristics are achieved on the basis of asymmetrical
and open wave guide technology, particularly that of micro-strip
technology, using foil circuitry or foil-like conducting
surfaces.
The azimuth omnidirectional antenna configuration elaborated in
Patent DE 41 13 277 proceeds exclusively from a foil as a
structural support, whereby the described antenna component is
subject to a capacitative top loading outside of the terminal
device container. In like manner, the azimuth omnidirectional
antenna configuration illustrated in Patent DE 41 21 333 starts
with an electrically non-conducting foil as a mechanical structural
support, whereby the main radiation direction with respect to the
elevations exhibits a slope of approximately (minus) -30.degree.
(degrees of angle); that is, it exhibits a negative elevation
angle.
SUMMARY OF THE INVENTION
Thus, the disadvantage of the conventional antenna configurations
is that they either are exclusively omnidirectional at the azimuth
level or radiate merely within the negative angle range.
The purpose of the invention described herein is to provide a
system integratable antenna component with the smallest possible
surface expansion having the most unidirective azimuthal
directional effect; that is, it provides the preferred coverage of
a spatial hemisphere as well as a limited angular shift within the
positive range of elevation angle.
This purpose is achieved by the invention described herein by the
characteristics of the identifying portions of Claim 1 and the
subordinate claims that refer back to Claim 1.
In the case of the antenna described in the invention and which can
be characterized as a radiating foil, we refer to a modified
.lambda./4 radiator [antenna] which is shorted on the one side
against ground. In order to achieve the most compact construction
the longitudinal conductor segment, which serves as the resonator,
is designed as .lambda./4. In this manner, the resonator becomes,
however, inductive and the vibratory condition is not fulfilled. At
the opposing end of the resonator on the side to be shorted, an end
capacitance is produced so that the resonance requirement
[condition] can be obtained. Said end capacitance is produced by at
least on additional conductive segment which is connects to the end
of the resonator lying opposite the side to be shorted and which
forms an open circuit [no-load] at its other end. The length of the
additional conductive segment determined by the vibratory condition
and thus the resulting resonance frequency of the entire structure.
Here, various design forms of the conductive segment at the end of
the resonator are conceivable for the realization of a defined end
capacitance. The end capacitance can be realized by one or several
circuits of appropriate lengths that do not necessarily have to be
parallel to one another or run to the resonator. All circuits can
likewise be laid out in whatever curvature and not exclusively
straight linear form.
By covering the antenna or the foil radiator foil using an
additional dielectric layer, which is not considered in the design
process, significant desensitization vis-a-vis other dielectrics in
proximity to the radiator (antenna) can be achieved. This is
important in that by integrating the foil antenna into radio
devices (dielectric effect) and by the affect that results by
holding the radio device in the hand, functionality is preserved
and the antenna is not detuned or maladjusted.
Since in this type of antenna the one side is shorted, there is
only one transmitting or receiving end. This results in a
dyssymmetry or the directive characteristics in the vibratory plane
of the electrical field vectors (E-planes) and thus in an angular
shift of the main transmission direction in said plane of
approximately 30.degree. in the line of sight on the shorted
transmitter side--transmitting end.
The electrical properties of these antennas; such as, for example,
quality, impedance bandwidth, gain and efficiency depend on the
size of the mechanical shortening attained (reduction), the breadth
of the resonator, the distance between the resonator and the end
capacitance circuit segments, the effective permissibility
[permitivitat] constants, the substrate thickness or the dielectric
loss angle.
By using the present invention, it is possible to install two or
more antennas for different wavelengths in a relatively small
space. An essential characteristic of the invention is that the
resonators realized using micro-strip technology for receiving the
microwaves are created shorter than .lambda..sub.g /4 and, as
already mentioned, the vibratory condition is no longer met. The
required end capacitances are realized by additional conductor
segments. An enlargement of the frequency bandwidth can be achieved
by additional antenna elements by electromagnetic coupling. This is
done by additional micro-strip circuits that are arranged at
certain intervals to the resonator and its end capacitances. It is
possible, using two or more resonators on a single substrate, to
receive several wavelengths, whereby the resonators can be
spatially arranged interleaved within one another and tuned to the
required frequency bands. The individual antennas need not be
arranged on one plane, but can also be arranged in layers. In this
manner it is also possible, that per layer several antenna
arrangements can be provided, so that more than two different
frequency bands are served. In this situation it is possible that a
mobile radio-telephone can communicate with different mobile
communications networks.
These and other features of the invention will be more understood
by reference to the following drawings:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1: An antenna pursuant to the invention with a resonator
connected to the ground layer and two conductor segments,
representing the end capacitances, abutting the resonators
bilaterally.
FIG. 2: An illustration in cross-section of the antenna as
described in FIG. 1.
FIG. 3: An antenna as described in FIG. 1 with only one conductor
segment creating the end capacitance.
FIG. 4: An antenna pursuant to FIG. 1, in which the conductor
section is situated on one side of the resonator.
FIGS. 5 and 6: An antenna with 4 and 3, respectively, conductor
sections forming the end capacitances.
FIG. 7: An antenna, whose end capacitance conductor sections are
not formed linearly straight, but angular.
FIGS. 8, 9A, 9B to 10: An antenna as shown in FIG. 2, in which
several resonators interleaved into each other are provided for the
purpose of increasing the frequency bandwidth.
FIG. 11: Two antennas, interleaved into each other as described in
the invention, for reception of two frequency bands.
FIG. 12: Two antennas as described in the invention and arranged on
a substrate for the reception of two frequency bands with one
supplemental coupler each for the increase of the respective
frequency bandwidth.
FIG. 13: View from above onto a planar-antenna for the reception of
two frequency bands.
FIG. 14: A cross-section illustration of an antenna as described in
FIG. 13.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an antenna as described in the invention with a
foil-like low-dielectric support (10), which is layered on one side
with a conductive structure (S) consisting of conductor sections 2,
3, and 4 running in straight lines and parallel to each other,
whereby the conductor section 3 is conductive and connected on one
side with a grounding surface (8), which in turn, as shown in FIG.
2, is in connection with the ground plane (1) by way of a
conductive coating of the cross-section area of the support
substrate (1). Instead of the conductive coating (12) the ground
layer (8) (design example not shown) can be connected to the ground
plane (1) by means of on or several terminal pins, which pass
through the substrate layer (10). The conductive coating of the
cross-section plane of the support substrate (10) shown in FIG. 2
does not necessarily have to run over the entire width of the
antenna, but it can impinge on a partial coating of the foil
cross-section plane [folienquerschnittsflache]. The conductive
sections (2, 3, and 4) are each arranged separated from one another
by a definite gap, whereby the conductive sections (2, 3, 4) each
are conductively connected by strip-like conductor section (7)
running diagonally in a defined section length- and width, whereby
the running diagonally conductive section is arranged at the
conductor section end of the antenna lying opposite the ground
contact (8). The conductor section (3) that is connected to a
ground layer (8) at a conductor section end and with the diagonal
strip-like conductor section (7) at its opposite end, is coupled at
site (9) with a signal wave conductor, in that the center conductor
(13) of a coaxial wave guide [wellenleiter] is arranged through an
aperture (15), which is arranged in the reverse ground plane (1),
centrally guided and coupled with the conductor section (3) at site
(9) on the longitudinal symmetry line of the of the conductor
segment, and the external conductor of the coaxial wave guide is
connected conductively with the reverse ground plane (1) to the
aperture rim (15).
The vibratory condition of the open and non-symmetrical wave guide
structure in the form of micro-strip technology is determined over
the geometric length and breadth of the conductor sections (2, 3,
and 4). The starting impedance of the micro-strip arrangement is
determined over the input coupling point (9) along the line of
symmetry of the conductor section (3), which in turn is dependent
on the resultant length of the conductor sections (2 and 4),
whereby the signal input and output coupling occurs at the point
(9) via a circular coaxial aperture or a slit or quadrilateral
shaped aperture.
Detuning of the antenna as a result of dielectric environmental
influences is compensated over the length of the conductor sections
(2 and/or 4), whereby the degree of detuning of the antenna as the
result of dielectric environmental factors is affected or minimized
by the application of a dielectric layer (11) of a defined
dielectric number as well as of a defined geometry.
The dielectric support layer (10) is particularly a polystyrol foil
having a layer thickness of 1 mm that is provided on the one side
over its entire area with a copper or aluminum foil of a layer
thickness of between 0.01 mm and 0.5 mm that forms the ground
plane. As shown in FIG. 2 the same polystyrol support is provided
with a foil-like structure (S) consisting of copper or aluminum
having a layer thickness of between 0.01 mm and 0.5 mm, and
consisting of the conductor sections (2, 3, 4) running in a
straight line, parallel to each other and separated by a
longitudinal gap. The dielectric layer (11) likewise has a layer
thickness of approximately 1 mm.
In a particular design form the antenna has a length L.sub.A of 199
mm and a width of B.sub.A of 40 mm. The length L.sub.A of the
ground plane (8) is 20 mm. The distance LB from the ground plane
(8) to the feeder point of the antenna (9) likewise is 20 mm. The
diameter of the aperture (15) is 4.1 mm. The length of the
conductor section forming the end capacitance K.sub.1 and K.sub.2
are measured at 82.6 mm and 56.7 mm. The length L.sub.A of the
conductor section (3) forming the resonator R measures 85.7 mm. The
width of the conductor section (2) is 11.5 mm, and the width of the
conductor section (4) is 9.5 mm. The width of the resonator
conductor section is 12 mm.
FIG. 3 shows an antenna as described in the invention in which
solely a conductor 10 section (K) running parallel to the resonator
conductor section (3) or to R forms the end capacitance.
FIG. 4 shows an antenna as described in the invention in which the
end capacitance is formed by two parallel conductor sections,
K.sub.1 and K.sub.2, which are arranged on one side of the
resonator conductor section R. Likewise, as illustrated in FIGS. 5
and 6, an antenna can be configured in which the resulting end
capacitance is achieved by three or four conductor sections,
K.sub.1 to K.sub.4.
FIG. 7 illustrates an additional design form of the antenna as
described in the invention in which the conductor sections (16 and
17) that form the end capacitance are not straight linear, but run
an angular course.
FIGS. 8 to 10 illustrate antennas in which the frequency bandwidth
of the antenna is adjusted or expanded by electromagnetic coupling
with supplemental conductor elements that are arranged on the same
dielectric support substrate. The antenna pursuant to FIG. 8
corresponds in its basic construction to the antenna shown in FIG.
3, wherein a U-shaped conductor section (19, 20, 21) inserts with
one of its arms (21) into the space between the resonator conductor
section (3) and conductor section (2), that forms the end
capacitance. The other arm (19) is connected with a supplemental
ground surface (18), which is correspondingly connected with the
ground plane (1) corresponding to the ground surface (9). FIG. 9B
corresponds in its basic structure to FIG. 1, whereby two
additional U-shaped conductor sections (23 to 28) are provided and
which each with its arm (27, 28) intrude into the space formed by
the conductor sections (2, R, 4).
FIGS. 9 and 10 illustrate other possible executions of the antenna
described in the invention, whereby the arrangement of the
additional conductor segments (30 to 38) whose coupling for the
purpose of enlargement of the frequency bandwidths is, in
principle, optional. It is also conceivable that the conductor
segments enmesh helically with each other, such that a long
parallel lead of conductor segments in a relatively minimal space
is obtained.
FIGS. 11 to 14 illustrate antennas, in which two antenna signals
can be coupled in and coupled out, whereby two frequency bands can
be simultaneously received or served by using only one foil
antenna. Through the variable layout of the resonator conductor
section R.sub.a and R.sub.b the resonance conditions are determined
in conjunction with the conductor sections 41a, b and 42a, b, as
well as points 43a, 43b of the outcoupling of the electromagnetic
waves. Through the interleaving of the two antenna arrangements
they can be arranged in the most confined space.
FIG. 12 illustrates another design form of an antenna using two
connections (51a, 51b) for dielectric wave guides, whereby only the
antenna layout illustrated in FIG. 8 with the respective
dimensioning are arranged alongside one another on one substrate
support.
FIGS. 13 and 14 illustrate a multilayer antenna in which the
antennas as described in the invention are arranged
sandwich-fashion over one another in several layers, whereby one
antenna corresponds to the vibratory/oscillatory conditions for the
frequencies of a particular mobile communications network. Through
the different resonance frequencies the antenna structures arranged
above one another interfere only minimally with each other. In
comparison to the arrangement shown in FIG. 2, less space is
required in the case of layering of the antenna structures, whereby
the antenna as described in FIG. 13 can be compactor and thus, the
mobile telephone device housing enclosing it can be designed to be
relatively small.
FIG. 14 illustrates the antenna as described in FIG. 13 in
cross-section. The conductive coating (12a, b) of the
cross-sectional area of the support substrate (10a and 10b) is
conductively connected with the structured layers S.sub.A and
S.sub.B. Such a conductive cross-sectional coating is feasible also
on the opposite side depending on the antenna construction.
It is clear that depending on the desired resonance frequency,
coupling, and tuning the respective geometries of the individual
conductor sections must be selected accordingly, whereby the
geometries of the conductor structures must sometimes be
empirically determined for achievement of the programmed
frequencies.
While the invention has been described with reference to the above
embodiments, it will be appreciated by those of ordinary skill in
the art that various modifications can be made to the structure and
function of the individual parts of the system without departing
from the spirit and scope of the invention as a whole.
REFERENCE DRAWING LIST
1 Ground Plane
2, 2a/b, 4, 4a/b Conductor Section as End Capacitance
6a/b, K, K.sub.I Resonator Conductor Section
5, 6 Spacing Gap between the end capacitance conductor sections and
the resonator conductor sections
7, 7a/b Resonator conductor sections with transverse conductor
section end capacitance
41a/b, 45a/b sections connecting end capacitance conductor
sections
8 Ground Surface; in conjunction with the Ground Plane (1)
9 Feeder Point of the Antenna
10 Dielectric Support Layer
11 Dielectric Layer
12 Conductive Coating of the Transverse Surface of the Support
Substrate
13, 13a, 13b Internal Conductor of a Coaxial Wave Guide
14, 14a, 14b Solder Point
15, 15a, 15b Aperture
16, 17 Conductor Section as End Capacitance in Angular Wave
Shape
18, 22, 29, 40b, 47 Additional Ground Surface; in conjunction with
the Ground Plane
19-21; 23,-28 Additional, essentially U-shaped Conductor
Section
30-35; 31', 33'
35', 48a/b-50a/b
36, 37, 38, 36' Conductor Section for Adjustment/Setting of the
Antenna [De]Tuning
37', 38', 40b
B.sub.A Width of the Antenna
L.sub.B Length of the Ground Plane B
L.sub.A Length of the Antenna
L.sub.B Distance of the Coupling-In Point from the Ground Surface
(8)
L.sub.R Length of the Resonator Conductor Section
L.sub.Ki Length of the End Capacitance Conductor Sections
L.sub.SP, L.sub.SPI Width of the Separation Gap
S, Sa, Sb Conductive Layer Structured as Micro-strip Circuits
* * * * *